Deck Tech again with the Trading Post

Deck-Tech-again-with-the-Trading-Post
So in continuation of brewing decks with Magic 2015, I have found a possible of an archetype that I played back in Mirrodin Besieged days of Standard. The deck is built around the four mana cost ‘Artifact Planeswalker’ as they call it, Trading Post. The one M15 card that made me reconsider this is Scuttling Doom Engine.

The engine in multiple copies can chain to the post’s third ability which is a very huge card advantage in the late turns. I just have to check which base color to use for this build. I initially considered Black, as the previous Trading Post Tezzeret build was Black w/ Blue. Here is a very rough draft of the deck:

Creatures
4 Scuttling Doom Engine
2 Indulgent Tormentor
3 Phyrexian Revoker
3 Pack Rat

Spells
4 Trading Post
4 Darksteel Ingot
2 Ratchet Bomb
4 Thoughtseize
3 Underworld Connections
3 Hero’s Downfall
3 Devour Flesh
1 Silence the Believers

Lands
4 Mutavault
1 Urborg, Tomb of Yawgmoth
19 Swamp

Black provides the spot removals needed to stop early aggression as well as hand disruption to prevent opponents from countering Post or Scuttling Doom Engine. I am not sure if Darksteel Ingot is really needed as a ramp artifact and later on used as a sacrifice in Trading Post.

My other plan is based on Green for Sylvan Caryatids, though I do not think the color would suffice.

Any inputs or ideas in mind regarding this card combo I’d really appreciate to read it. Just post them in the comment box below. Thanks in advance.